/* DESC: This script implements a TCP server which can be used to control the DIO ports.
 * Copyright (C) 2012 NetModule AG, Switzerland
 */

MAX_CONNECTIONS = 1;
PORT = 2158;
ADDR = "";
NUMERIC = 0;

string handle_plain (string msg) 
{
    if (left(msg, 5) == "out1=") { 
        state  = (int) substr(msg, 5, 1);
        if (state != 1) state = 0;
        nb_dio_set("out1", state);
        return "OK\n";
    } else if (left(msg, 5) == "out2=") { 
        state  = (int) substr(msg, 5, 1);
        if (state != 1) state = 0;
        nb_dio_set("out2", state);
        return "OK\n";
    } else if (left(msg, 4) == "out1") { 
        state = nb_dio_get("out1");
        return sprintf("out1=%d\n", state);
    } else if (left(msg, 4) == "out2") { 
        state = nb_dio_get("out2");	
        return sprintf("out2=%d\n", state);
    } else if (left(msg, 3) == "in1") { 
        state = nb_dio_get("in1");	
        return sprintf("in1=%d\n", state);
    } else if (left(msg, 3) == "in2") { 
        state = nb_dio_get("in2");	
        return sprintf("in2=%d\n", state);
    } else {
        return "ERROR: invalid command\n";
    }
}


/* handle legacy numeric mode */
string handle_numeric (string msg) 
{
    if (left(msg, 5) == "10000") {
        /* get request */
        return sprintf("%d%d%d%d",
                       nb_dio_get("in1"),
                       nb_dio_get("in2"),
                       nb_dio_get("out1"),
                       nb_dio_get("out2"));
    } else {
        /* set request */
        x = substr(msg, 0, 1);
        if (x == "1") {
            nb_dio_set("out1", 1);
        } else if (x == "0") {
            nb_dio_set("out1", 0);
        } else {
            return "ERROR: invalid command\n";
        }

        x = substr(msg, 1, 1);
        if (x == "1") {
            nb_dio_set("out2", 1);
        } else if (x == "0") {
            nb_dio_set("out2", 0);
        } else {
            return "ERROR: invalid command\n";
        }
    }
    return "";
}

void usage()
{
    printf("Usage: dio-server.are [-n] [-i <ifc>] -p <port>\n\n");

    printf("Options:\n");
    printf("\t-n              operate in numeric hex mode\n");
    printf("\t-i <ifc>        bind to interface <ifc>\n");
    printf("\t-p <port>       listen on TCP port <port>\n");
    printf("\n'");

    printf("Available commands:\n");
    printf("\tSet output port:              out<1|0>=<1|0>\n");
    printf("\tGet status of input port:     in<1|2>\n");
    printf("\tGet status of output port:    out<1|2>\n");
    printf("\tStop server:                  quit\n");
    printf("\tDisconnect from server:       bye\n");
    printf("\n");
    exit(1);
}


/* get options */
for (i=1; i<argc; i++) {
    if (argv[i] == "-n") {
        NUMERIC = 1;

    } else if (argv[i] == "-i") {
        ADDR = nb_ifc_address(argv[++i]);
        if (ADDR == "") {
            printf("ERROR: invalid interface\n");
            exit(1);
        }

    } else if (argv[i] == "-p") {
        PORT = (int) argv[++i];
        if (PORT <= 1024 || PORT >= 65536) {
            printf("ERROR: invalid port %d\n", port);
            exit(1);
        }

    } else {
        usage();
    }
}

port = (int) argv[opt];

/* create server socket */
sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if (sock < 0) {
    printf("ERROR: Unable to open socket\n");
    exit(1);
}

/* bind to port (and address) */
ret = bind(sock, PORT, ADDR);
if (ret == -1) {
    printf("ERROR: Unable to bind port %d\n", port);
    close(sock);
    exit(1);
}

/* listen on socket */
ret = listen(sock, MAX_CONNECTIONS);
if (ret == -1) {
    printf("ERROR: Unable to listen\n");
    close(sock);
    exit(1);
}

printf("Listening for connections (addr %s, port %d)\n", ADDR, PORT);

quit = 0;
timeout = 10;
while (!quit) {
    /* check if new client has connected */
    client = accept(sock);
    if (client < 0) {
        printf("accept failed\n");
        sleep(1);
        continue;
    }
    printf("New client connected\n");
    
    while (1) {
        /* wait for client socket data  */
        rv = select(client, timeout);

        if (rv == -1) {
            printf("ERROR: select failed\n");
            close(sock);
            exit(1);
        } else if (rv == 0) {
            /* nothing received */
            //printf("timeout\n");
        } else {
            /* received something */
            msg = recv(client);
            if (left(msg,4) == "quit") {
                printf("Received quit, terminating server\n");
                quit = 1;
                break;
            } else if (left(msg,3) == "bye"){
                printf("Received bye, closing client connection...\n");
                break;
            } else if (msg != "") {        
                if (NUMERIC == 1) {
                    answer = handle_numeric(msg);
                } else {
                    answer = handle_plain(msg);
                }
                if (answer != "") {
                    send(client, answer);
                }
            }
        }
    }
    close(client);
}

close(sock);
exit(0);